Topic 8(Chemical analysis

Question 1

Pure substance

Answer 1

usually means that nothing has been added to it, meaning it’s in it’s natural state.
In chemistry it means that it only contains one compound or element throughout.
They will also melt or boil at a specific temperature

Question 2

Formulations

Answer 2

useful mixtures with a precise purpose that are made by a formula.

Question 3

Examples of formulations.

Answer 3

Pigment- gives off curtain colours.
Solvent- used to dissolve components and change the viscosity.

Question 4

Why are formulations important

Answer 4

used in the pharmaceutical industry to(for example) drug a curtain part of the human body at the right concentration.

Question 5

Test for Chlorine

Answer 5

Chlorine bleaches damp litmus paper, turning it white

Question 6

Test for oxygen

Answer 6

If you put a glowing splint inside a test tube containing oxygen, the oxygen will relight the glowing splint.

Question 7

test for carbon dioxide

Answer 7

shaking carbon dioxide with an aqueous solution of calcium hydroxide(known as lime water) causes the solution to turn cloudy.

Question 8

test for hydrogen

Answer 8

If you hold a burning splint at the end of a test tube containing hydrogen, you’ll get a squeaky pop